Abstract: Aiming at the status of shortage of high quality coking coal resources and disordered supply of coal, and less understanding of coal property, taking dou ble furnace design and constant torque as the core technology, the MJS-1 giesler fluidity testing machine with duble furnace was developed, which included many parts, such as transmission and mixing system of coal retort, detecting system of constant torque, convert heating system, automatic counting print and control system, inelig ent control system. This testing machine improved the accuracy of coal retort system and optoelectronic system, and could realize the coal quality analysis detection fu nction. Compared with the existing instrument and import instrument, the results showed the good repeatability of characteristic temperature and the maximum fluidity, t he precision met the requirements that the characteristics of temperature average was not more than 8。C, and average value of the maximum fluidity was not more tha n 20%, which were completely conform with the industrial standard of MT /T 1015- -2006.